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<head>
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    <title>Document</title>
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           .row {
               background-color: pink;
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<body>
    <div class="container">
        <div class="row">
            <div class="col-md-4">
                <div class="row">
                    <div class="col-md-4">a</div>
                    <div class="col-md-4">b</div>
                    <div class="col-md-4">c</div>
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            <div class="col-md-4">2</div>
            <div class="col-md-4">3</div>
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</body>
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